Traffic control apparatus



March 15, 1966 H. A. WILCOX TRAFFIC CONTROL APPARATUS 6 Sheets-Sheet 1 Filed Aug. 4. 1960 O 4 6 6 f Ru nG L A N H NEW 6 w W M 6 ES v S 3 R.Y G 6 M fix 5 6 MASTE R CONTROL STANDBY CYCLIC TIMER @NDBY CONTROLLER INVENTOR. HARRY A.WlLCOX C maa; Y

ATTORNEY March 15, 1966 H. A. WILCOX 3,241,110

TRAFFIC CONTROL APPARATUS Filed Aug. 4. 1960 6 Sheets-Sheet 2 OTHER LOCAL CONTROLLERS v PF3 W I:

(SPIKE PULSE SQUARE PULSE mm [SHAPER o SHAPER o i SPIKE PULSE no? PFZ $HAPER o y W COINCIDENCE COINCIDENCE GATE 3 V COINCIDENCE GATE STANDBY 5 5 cel CONTROLLER\ I INVENTOR.

F 3 HARRY A. WILCOX u BY ATTORNEY March 15, 1966 Filed Aug. 1960 H. A. WHLCOX TRAFFIC CONTROL APPARATUS 6 Sheets-Sheet 5 TO POSITION l BANK 55 TO POSITION 3 BANK 55/ TO CONTACT 53 T0 MOTOR I56 AND SPLIT RING I55 TO CONTACT 54- ,INVENTOR HARRY A. WILCOX mw V M ATTORNEY March 15,, 19% H. A. WILCOX TRAFFIC CONTROL APPARATUS 6 Sheets-Sheet 5 Filed Aug. 4. 1960 INVENTOR HARRY A. WILCOX ATTORNEY March 15, 1966 H. A. wlLcox TRAFFIC CONTROL APPARATUS 6 Sheets-Sheet 6 Filed Aug. 4, 1960 INVENTOR HARRY A.W|LCOX FIG. I2

ATTORNEY United States Patent 3,241,110 TRAFFIC CONTROL APPARATUS Harry A. Wilcox, Westport, Conn., assignor, by mesne assignments, to Laboratory for Electronics, Inc., Boston, Mass, a corporation of Delaware Filed Aug. 4, 1960, Ser. No. 47,556 16 Claims. (Cl. 340-41) The present invention relates to traffic control systems and apparatus and more particularly in its primary aspect relates to an improved traffic controller having a novel printed circuit construction providing unusual compactness, low cost and convenience of adjustments in such controller.

The invention further relates to standby traffic control apparatus adapted to cooperate with normal traffic control apparatus for emergency operation of traffic signals, and also relates to a traffic signal controller including the normal and standby control features.

This invention additionally relates to improved traffic control apparatus having a plurality of offset means and indicator means for indicating the offset in actual use. The term offset is well understood in the traffic control field as referring to the displacement of the traffic signal time cycle of an individual local signal controller from a cyclic time reference point which may serve as a common reference or zero offset from which several controllers along a street may have different offsets in any one system of offsets, and each controller may have different adjustable offsets from which any one may be selected locally or remotely for use, as more fully described below.

This invention also relates to a traffic control system utilizing the improved printed circuit controllers or control apparatus.

Traffic control apparatus according to the invention is well adapted for an individual traffic signal controller, or to master-local traffic control systems in which local signal controllers are controlled in part by a master controller.

Traflic control apparatus and systems are well known in the art. Cyclic timing means is generally used for controlling the switching of the traffic signals as desired, and such cyclic means may for example include a rotating timing dial assembly including a drum having slots for receiving pins or keys which cooperate with control switch means including stepping switches or cam and switch assemblies for sequential control of the traffic signals. The pins or keys are adjustably positioned in slots or holes with respect to one another on the drum, for example, to vary the time sequence of the traffic signals.

This method of adjustment has the obvious disadvantage of requiring that a large number of slots be available in the drum for all possible adjustment positions even though only a few of such positions will be used at any one time or in a particular controller. The drums of such dial assembly are quite bulky and expensive and require electric motors of substantial power.

Emergency operation of the trafiic control system in the past has included the use of auxiliary flashing equipment to automatically flash the intersection control signal, or the use of an additional local controller as an auxiliary or reserve controller to operate the intersection control signal cyclically.

The use of auxiliary flashing equipment may defeat the primary purpose of signalization of a heavily traveled main artery and the cross streets. The use of an additional local controller as an emergency controller is costly since it requires two local controllers installed at each signalized intersection with only one local controller actually in use at any one time. Furthermore the disadvantages of these older systems are increased when applied to a traffic system in which it is desired to have coordination between intersections even when the standby controllers are operative.

Traffic control apparatus is already known as having multiple individually selectable offset means and individual indicator means for indicating which offset means is selected, but particularly where there is a gradual change of actual offset from one selected offset to another there has been a great need for some means of indicating the actual offset during such gradual change as well as in its steady condition.

Accordingly, it is one object of this invention to provide a low cost, compact and serviceable printed circuit traffic controller apparatus for cyclically controlling trafiic signals.

Another object is to provide a printed circuit traffic controller with adjustable single means for determining any one of many points within the traffic signal cycle in which the operation of the traffic signals is desired to be controlled.

Another object is to provide printed circuit control apparatus having a reference or rest position so that a system of such individual controllers at individual trafiic intersections may be coordinated and adjusted with respect to each other and a common reference point.

Another object is to provide an improved traffic signal controller having a standby controller provided with a reference or rest position and being adapted to cooperate with a normal local controller so that when said normal controller is effective the standby controller is ineffective and will home to its rest position so that when made effective, the standby controller will start from its rest position.

A still further object is to provide an improved traffic control apparatus in which a printed circuit standby timer cooperates with a normal timer and in which certain elements are used in common by both timers for control of traffic signals.

A still further object is to provide a single indicating means which will indicate the present offset in use in a local traffic controller which has a plurality of selectable offset-s.

Another object is, in a local traffic controller having a plurality of select-able offset means, to provide a single offset determining means which gradually changes to correspond to any selected offset and single indicator means cooperating with said offset determining means for indicating the present offset in use whether steady as selected or in process of gradual change from one selected offset to another.

The foregoing objects and others are accomplished and disadvantages of the prior art are overcome by various aspects of the present invention which are indicated below and referred to in the detailed specification.

From one aspect, the invention provides a novel improved cyclic means for a local traffic controller using a printed circuit panel which is cyclically scanned to periodically cont-r01 the traffic signals.

From a still further aspect, the invention provides a printed circuit local traffic controller having a plurality of printed circuit contact elements and means for energizing certain of said contact elements, such as by selectable or adjustable means for example, and for cyclically scanning all of the contact elements sequentially to derive pulses or control signals at time intervals as the scanning means scans the certain energized contacts.

From another aspect, the printed circuit local traffic controller provides a controller in which maintenance repair time and cost is reduced by the use of the printed circuit cyclic means which is easily observable, removable and inexpensively replaced.

From a still further aspect, the invention provides a compact improved traffic control apparatus to provide auxiliary standby or emergency cyclic timing for operation of a cyclic mechanism of a local or primary traffic controller in the event that the normal cyclic timing apparatus of the local or primary controller should fail to function as by failure of the normal cyclic timer in a local traffic controller or by failure of -a master controller in a master controller traffic control system so as to cause failure of the local cont-roller of the traflic control system.

From a still further aspect, the invention provides a novel single indicator means for indicating the actual percentage offset in use in a local controller which has a plurality of selectable offsets and for indicating the instantaneous or current offset during gradual change from one selected offset to another.

Another aspect of the present invention provides a compact and inexpensive auxiliary or standby cyclic timer for a primary traffic controller which may be employed as auxiliary or emergency equipment and provides an adjustable time cycle, for distribution of right of way between trafiic flows, for operation of a signal sequence switch of a primary local traflic controller whereby the distribution of the time of the cycle may be simply and conveniently adjusted and in which certain of the components of the primary local traflic controller are used in common by the primary controller and the auxiliary cyclic timer.

The standby cyclic timer of this invention is compact and inexpensive while also capable of performing varied functions in cooperation with elements of normal controller to ideally perform the functions of a standby controller. However, the features of the novel standby controller of this invention suggest its use as an independent local controller as well as a standby controller.

Furthermore, one aspect of the invention provides that the standby timer have outputs capable of having substantially the same cooperation with the signal sequence switch as is normally provided by the normal timer.

From one aspect, the invention provides two printed circuit commutators each having a multiplicity of contacts which are interconnected and in which cyclic scanning means are associated with one commutator and adjustable means associated with the other commutator so that electrical coincidence or correspondence between the scanning and adjustable means results in control of the traflic signals.

From another aspect, the present invention in a preferred embodiment provides such a controller in which a printed circuit board having a plurality of contacts printed on an insulating board is utilized; a source of power is connected to certain of the contacts as determined by an adjustable means. A motor driven electrical contact brush assembly scans the contacts and closes an electrical circuit as it passes over the certain contacts. Power flowing through this electrical circuit may then control the traffic signals at time intervals in dependence upon the adjustable means. The brush assembly may either supply power to or derive power from the certain contacts.

Another further advantageous aspect of the present invention is the provision of an automatic homing device for automatic return of the auxiliary cyclic timer to a certain predetermined position of its cycle when the primary controller returns to normal operation and resumes control of its signal sequence switch. Indicator means are also utilized to indicate the percentage of the cycle that the standby cyclic timer is in at any time relative to its home position.

A preferred embodiment of the invention combining its several aspects provides a printed circuit trafiic controller in which the printed circuit and a scanning means serve as a cyclic means having many advantages in simplicity, cost and ease of maintenance and repair of traffic apparatus.

Manually adjustable brush means cooperate with various segments of the printed circuit commutator to determine points within the traffic signal cycle at which the trafiic signals are controlled. The connection of these brushes to calibrated dial type, knob means provides an easily available manual adjustment while also indicating the percentage of the cycle at which the tratfic signals are to be controlled. As the scanning means scans the printed circuit contacts, sufiicient control signals may be derived from the printed circuit to correspond with the normal number of control signals from a normal controller so that the printed circuit controller may operate as a standby controller with a normal controller and both may utilize the same trafiic signal sequence switch for control of the trafiic signals by either. In addition a reference, rest or home position means is provided on the printed circuit timer (which is available whether the printed circuit controller is used independently or as a standby controller) to permit coordination between a plurality of printed circuit controllers in a trafiic control system. Two indicators are disclosed. One indicator indicates the present percentage of the cycle of the printed circuit timer and the other is a single indicator which indicates the present offset in a local controller having a plurality of olfsets and means for selectively determining which of these offsets is to be effective and providing for a gradual change from one offset to another. The indicator means indicates the present oifseteven during the gradual change.

My invention and other objects will be more clearly understood by reference to the claims and the following detailed specification and drawing of which:

FIG. 1 represents in block diagram form a master controller trafiic control system including a master controller, a local trafiic controller and a standby cyclic time! with potential connections between the standby cyclic timer and the signal sequence switch of the local traffic controller.

FIG. 2 represents, in simplified schematic circuit form the standby cyclic timer represented in block form in FIG. 1.

FIG. 3 represents partly in block form and partly in simplified schematic circuit form a master controlled traflic control system with a standby cyclic timer associated with a local traffic controller.

FIG. 4 illustrates the preferred form of printed circuit employed in the standby cyclic timer. FIG. 4A illustrates a section of printed circuit segments 151 (FIG. 4) at about the ten oclock position.

FIG. 5 illustrates one form of face plate or panel that may be employed for the standby cyclic timer and other apparatus of the invention.

FIG. 6 illustrates, in side view and in partly cut-away form, the standby cyclic timer and other apparatus of FIG. 5.

FIG. 7 is an exploded view of the selection assembly for distribution of the time cycle or split of the time; cycle.

FIG. 8 is a face view of a disc with a concentric or annular conductor and brush.

FIG. 9 is an exploded view of the rotating brush assembly. FIG. 9a illustrates a side view oficoupling spring 226. i

FIG. is a front view of the rotating brush unit shown above in FIG. 9 in side view.

FIGURE 11 is a schematic drawing illustrating several modifications and additions of elements to the standby controller of FIG. 3 to form an independent local controller.

FIGURE 12 illustrates one form of a resistance-capacitance timing circuit which may be employed for timing certain steps of the controller of FIG. 11 if desired.

Referring to FIGURE 1 in more detail, a block diagram of the present invention is presented in the form of a master controlled trafiic control system. Block 30 represents a master controller which controls the time cycle and thus the normal cyclic timer block 40 of a local traffic controller. Such master controller and normal cyclic timer may be of any form known in the art.

The master controller and normal cyclic timer may be in the form illustrated schematically in FIG. 3 which is the subject matter of US. patent application S.N. 510,926 filed May 25, 1955 for John L. Barker and assigned to the present assignee, and subsequently issued as Patent 2,989,728 on June 20, 1961. Alternatively, for example these elements may be of the type disclosed by John L. Barker in his US. Patent 2,542,978 issued February 27, 1951 under the title Trafiic Control Apparatus.

The normal cyclic timer 40 may also be in the form of a standby cyclic timer illustrated in simplified form in FIG. 2 and in block form in FIG. 1 as block 52.

The combination of block 51 the homing control to local zero position and block 52 the standby cyclic timer is here referred to as a standby controller, and is illustrated in simplified schematic form in FIG. 2 and described with reference thereto.

The standby controller may be called an auxiliary controller or an emergency controller since the standby controller, in its preferred form is generally employed as a substitute controller to perform certain functions normally performed by the normal cyclic timer in cooperation with the master controller. However as will appear in FIGURES 2, 11 and 12, the standby controller disclosed herein may also be independently used as a local controller.

Referring to FIG. 1 in more detail a block diagram of the normal cyclic timer 40 is represented as having a ground supply (shown as a minus lead) via normally closed contact 41 which contact is illustrated in FIG. 3 more fully with respect to the illustrated normal cyclic timer and is also illustrated in FIG. 2 more fully with respect to the illustrated standby controller. Block 40 is represented with two output connections, one each to positions one and three, with respect to the lowermost position, of a four position line switch bank 43. The outputs to the line switch bank 43 are represented as passing to arm or wiper 44, when in positions one and three, through the normally closed contact 45 to signal sequence switch 60. Contact 45 is illustrated and more fully described with regard to its specific function in FIG. 3.

Signal sequence switch 60 may include a motor magnet and/or stepping switch and associated banks of line switches of the familiar telephone line switch type, for example, of which line switch banks 43 and 55 are assumed included, with a motor magnet employed to advance the arms or wipers of the line switch banks cyclically, as desired, step by step, from one position to the next.

FIG. 3 illustrates several line switch banks, all of which may be assumed to be included in the block 60, along with the line switch banks 43 and 55.

The broken line 61 extending to lines 61a and 61b indicating that the arms or wipers 44 and 56 of banks 43 and 55 respectively are advanced from one position to 6 the next by a motor magnet of the signal sequence switch 60.

Outputs of block 60 are represented by lines 63 and 64, each line representing a group of leads connected to signal lamps 65 and 66. Signal lamps 65 and 66 may each include a red (R), yellow (Y) and green (G) signal for use at an intersection of two or more roadways and particularly for control of vehicle traffic in the conventional manner.

Standby controller 50, including homing control to local Zero position, block 51 and standby cyclic timer 52, represents, in block form, the standby controller illustrated in simplified form in FIG. 2, with the face plate in FIG. 5 and side view of the unit in FIG. 6 with exploded views of some of the interior components in FIGS. 7, 8, 9, and 10.

Block 51, completes circuitry to drive standby cyclic timer 52 to a local zero position when normal operat-. ing auxiliary circuitry is opened as more fully illustrated and described with reference to FIG. 2.

When normally open contact 53 is closed, an auxiliary circuit is completed providing power to operate a motor for operation of the standby cyclic timer which auxiliary circuit and cyclic timer may be used for traflic signal energizing purposes. This standby controller is illustrated and described with reference to FIG. 2 and its association with a normal cyclic timer in a tralfic control system is illustrated and described with reference to FIG. 3.

A positive power supply is applied through arm 56 to standby cyclic timer in positions one and three of line switch bank 55 which positive power is fed to output 167, as more fully described below and through normally open contact 54, when closed, to block 60 thus providing auxiliary positive power to block 60 in lieu of a normal positive power normally supplied by block 40. Thus it is seen that the signal sequence switch 60 of a local controller may be controlled by either a normal cyclic timer of the local controller or by a standby cyclic timer as desired.

Referring to FIG. 2 a simplified form of standby controller is illustrated, in broken line box 50, with printed circuit electrical contact elements or segments 151 arranged in circular form, a printed circuit commutator 152, arranged in circular form, and a printed circuit ring 153 within the printed circuit commutator. Two electrical contact elements or brushes B1 and B2 are represented as being driven by a motor 156 in a clockwise direction. The two brushes are joined at the top and provide a conductive path between the ring 153 and the individual printed circuit segment of the commutator 152 then contacted by the brush B1 in its rotary sweep.

Thus the brushes, as driven by the motor, scan the printed contact elements to derive or control power from certain of the individual elements to perform signal switching as will appear hereinafter.

A second ring, 154 and a split ring 155 are illustrated with a set of two brushes B3 and B4 joined at the top so as to provide conduction between the ring 154 and the split ring 155.

There may be, for example, 50 individual segments included in the printed circuit electrical contact elements or segments 151 and thus 50 individual printed circuit commutator segments 152, with each individual segment of 151 singularly connected as at to a corresponding individual segment of 152; only four such connections as shown at 158, 159, 160 and 161 for example are shown in FIGURE 2, although the connections between the two segmented circuits are fully illustrated in FIG. 4 in their preferred form.

Two adjustable brushes 162 and 163 are provided, each brush to contact one of the segments of 151 with brushes 162 and 163 connected to the positions 1 and 3 of line switch bank 55 via lines and 171 respectively. The brushes 162 and 163 are arranged so that the brushes may, if desired, contact the same segment or different segments of 151, although normally the brushes would be set on different segments.

A master switch 164 provides a means of stopping motor 156 as desired by opening the operating circuit. This switch may be locally or remotely located. The selector switch 165 provides for selection of operation of the motor driving means 156 and with the master switch closed, as illustrated the selector switch 165 provides for automatic operation, with automatic homing upon termination of operation in the upper position as illustrated, which would be the usual position for standby operation; in the middle position of switch 165 constant operation, of the motor is provided; in the lowermost position of the switch 165, the motor can be manually stopped after first homing to its local zero position even though standby operation is called for.

In the upper position of the selector switch 165 the motor will drive the brushes B1, B2, B3 and B4 to a local zero position, indicated by the gap 155 in the ring 155, when power via contact 53 for the automatic drive of motor 156 is discontinued. Homing power is provided on wire 174.

The upper position of selector switch 165 is illustrated as connected to a contact 53 of a relay PR illustrated in phantom form. The contact 53, which is illustrated in its normally open position, may be a manual switch of the single pole, double throw type. However, in the control system, as presented, this contact is operated by a relay, PR, which also operates contacts 54 and 45 and contact 41, the companion contact to contact 53.

When relay PR is deenergized contact 41 is closed providing a ground connection to the normal cyclic timer, as represented in FIG. 1, and contact 45 is closed which provides an output connection from the normal cyclic timer to a signal sequence switch 60 via the line switch bank 43 when the wiper 44 is in position 1 or position 3 of the bank 43.

The particular use of the relay PR and this associated circuitry is more fully explained with reference to FIG. 3 where circuitry of one form of local traific controller is illustrated.

With the relay PR energized contacts 53 and 54 are closed and, as illustrated, the motor 156 would be energized from alternating current (A.C.) power, represented by a plus in a circle, through the motor 156, switch 164, lead 166, segment 173 of selector switch 165, contact 53 to ground.

The brushes B1, B2, B3 and B4 would be driven in a clockwise direction and when the brush B1 scans or contacts the commutator segment or contact element of 152 that is connected to the segment or contact element of 151 to which the adjustable brush 162 is connected and wiper 56 of bank 55 is in position 1, a circuit is completed from AC. power through wiper 56 of bank 55, position 1 of bank 55, line 170, brush 162, the segment of 151, the lead between the said segment of 151 and the corresponding segment 152, the brush B1, brush B2, concentric ring 153, lead 167, contact 54 to relay PD to ground. The relay PD may be similar to the relay PD in FIG. 3 or may be a motor magnet or other repeater relay that may be found in the signal sequence switch 60, for example.

Thus the relay PD may be energized, so that, referring to FIG. 3 and fully explained below with reference thereto, a means to advance the wiper arms of the several banks of line switches including the arm 56 of bank 55, may be activated. As the brushes B1 and B2 continue to rotate clockwise the brush B1 leaves the said segment of 152 and the circuit energizing relay PD is broken and the relay becomes deenergized.

While clockwise rotation of B1 and B2 is suggested above, it will be obvious that they may be rotated counterclockwise.

The only requirement being that the relative directions of rotation of B1 and B2 with respect to the segments of 151 and their brushes be such as to provide a coincidence or correspondence of segments on each circular configuration of contacts.

A similar circuit is completed via position 3 of bank 55 and adjustable brush 163 when the brush B1 contacts the segment of 152 which is connected to the segment of 151 to which brush 163 is connected and the wiper 56 is in contact with position 3 of bank 55.

While it is obvious that while power is derived by the brushes through the printed circuit from the positive supply, it will be equally apparent that the brushes may be connected to the positive source and the printed circuit segments be grounded. Reference to a scanning of the contacts is intended to encompass both such cases and further include other than direct brush contact, for example, a capacitive scanning of the printed circuit.

Thus power pulses or signals may be produced through these circuits to momentarily energize relay, such as PD, as illustrated.

By adjusting the position of the adjustable brushes 162 and 163 and by rotating the brushes B1, B2, B3 and B4 by motor 156 slowly, of the order of one revolution per minute, for example, the pulse through position 1 of bank 55 and brush 162 may be provided at, for example, 14 percent of the cycle from the zero homing position and a pulse may also be provided through position 3 of bank 55 and brush 163 at, for example, 48 percent of the cycle from zero homing position. By adjusting the brushes 162 and 163 as desired the pulse through position 1 may occur at any percentage point in the entire cycle and the split of the cycle, that is the relation between the two pulses, relative to the time of the entire cycle may be adjusted as desired.

The percentage by which the pulse through position 1 and brush 162 is offset from the zero point relative to the control cycle may be used as an offset of the cycle between individual controllers while the pulse through position 3 and brush 163 may be used to split the time of a trafiic cycle between a north-south green east-west red phase and an east-west green north-south red phase. It will be appreciated that more than two such brushes may be utilized. For example, three such brushes would be employed in a standby controller which controls the intersection of three streets. One position will determine A-green, one for B-green and one for C-green.

In order that the standby cyclic timer may start from a known position, provision is made to drive the brushes B1, B2, B3 and B4 to a known or local zero position and stop the motor 156 at the zero position. This is accomplished by providing a ground connection 174 to the ring 154 and a connection from ring via lead 166 and switch 164 to motor 156 to AC power.

Thus when the contact 53 opens, as by deenergization of relay PR, an alternate ground is supplied to the motor 156, if the brush B4 is making contact with the ring 155, from the ring 154, brush B3, brush B4, ring 155 and through to the motor 156, as described. If the brush B4 is in the insulated or open section 155 of the ring 155, as illustrated, the motor will stop. If the brush B4 is in contact with the ring 155 the motor will drive the brushes until the brush B4 breaks contact with the ring 155 and rides in the open or on the insulation, at which time the energizing circuit for the motor 156 is broken and the motor stops. This action has been referred to as homing control to local zero position.

In the second position of selector switch 165 referred to as a DRIVE position, the standby motor is continuously driven since ground is supplied to the second position of switch 165, through the switch to 173 and lead 166 to the standby motor. In this position, therefore, a system of trafiic controllers may be provided in which each standby timer may be continuously driven in synchronism so that should the master or a repeater for different parts of such system fail at diiferent times, all standby con- 9 trollers will be in operation and in synchronism with each other even though some of such controllers have been energized at different times.

The third position of the selector switch 165 will allow a repairman to manually stop the standby controller in the event that switch 164 is not provided.

FIGURE 3 schematically illustrates the cooperation of particular elements of a local traffic controller with the standby controller. However it will be appreciated that the standby controller may itself be a traffic cont-roller and also may be adapted to operate with other traffic controllers.

Referring now to FIG. 3 in more detail, the three windings 31, 32 and 33, indicate an alternating current three phase generator source and are shown schematically included in broken line box 30, representing a master controller in the upper left of the drawing.

The RF leads indicate that this three phase current is supplied to a plurality of local traffic controllers so that a master-local traffic control system is provided.

Below the three windings 31, 32 and 33, are three additional windings 34, 35 and 36, which form the rotor of a three phase differential generator, for example.

The stator (not shown) of such three phase differential generator will be energized from the RF lead as is well known in the art. The leads VF from the rotor therefore carry three phase energy which is derived from the RF source and related thereto in dependence upon motor 37 as will appear below.

A variable speed motor 37 is represented below the rotating three phase windings and is represented as being driven mechanically by the motor 37 by the shaft 37.

It will be appreciated that the motor 37 may have a low speed output, provided by gearing or otherwise, as desired, to rotate the rotor windings 34, 35 and 36 at speeds of the order of one revolution in 40 seconds to one revolution in 120 seconds to derive a time cycle of the order of 40 seconds to 120 seconds, for example, with one revolution of the rotating rotor being equal to one time cycle of the system.

It will be understood by those skilled in the art that when a three phase rotor winding is rotated with respect to a three phase stationary winding the A.C. three phase output of the rotated winding (VF) will bear a phase relationship to the A.C. three phase output of the stationary winding (RF). This phase relationship between the two three phase outputs is progressively changing and by employing the output of the fixed or stationary winding as a reference output RF the output (VP) of the rotated winding will be slowly and progressively shifting in phase with respect to the reference output (RF) periodically, the time between phase coincidence being determined by the speed with which the rotated winding is rotated by the variable speed motor. This time between phase coincidences between the output RF and VF may be varied as by varying the speed of the motor 37 from 40 seconds to 120 seconds for example and thus such time between phase coincidences may be employed to time a traffic signal cycle for a traffic control system.

The switch 38, illustrated open, may be manually or automatically controlled, and when closed completes a circuit via lead 39 to energize a relay, OS, for example, associated with the local controller. The lead 39 may be extended to other local controllers, as desired.

Connected to the three phase reference output RF via leads 71, 72 and 73 are three 360 degree potentiometers PR5, PR6 and PR7. On each of the potentiometers are three taps 120 degrees apart with one tap of the taps on each potentiometer connected to one of the leads 71, 72 or 73 as for example potentiometer PR6, which is typical of the other potentiometers PR and PR7, and which has its upper tap 74 connected to lead 71, its tap 75, which is 120 degrees clockwise from tap 74, connected to lead 73 and its tap 76, which is 120 degrees clockwise from tap 75, connected to lead 72.

Each potentiometer has two brushes each displaced 180 degrees apart, which brushes are jointly adjustable as desired to positions 180 degrees apart on the 360 degree resistance, with each brush insulated from the other and connected to a separate ring, as for example brush 79 connected to inner ring 80 and brush 81 connected to outer ring 82 in potentiometer PR6.

With the potentiometers PR5, PR6 and PR7 connected to the lines RF as illustrated, it may be assumed that the upper tap, or tap 74 of PR6 for example, is the zero position on the 360 degree stator, and that the brush 79 determines the position of the brushes relative to zero.

The relay OS controls the contacts 84, 85, 86 and 89 so that either the rings 80 and 82 of PR6, connected to contacts and 89 respectively are connected to coil 90 of transformer T3 or the inner ring of PR5 connected to contact 84 and the outer ring of PR5, connected to contact 86 are connected to coil 90 of transformer T3, according to the position of the respective sets of contacts. Relay OS contacts are illustrated in their normal condition with relay OS deenergized thus the potentiometer PR6 is connected to coil 90.

The potentiometer PR7 is mechanically connected to the reversible motor RDM so that its brushes may be rotated by the motor RDM. The brushes of potentiometer PR7 are connected to the coil 91 of transformer T2.

If for example the tap 74 of potentiometer PR6 were arbitrarily designated the zero position and the brush 79 were adjusted to contact the 360 degree potentiometer at tap 74, with the brush 81 displaced 180 from such position, then the relationship between the three phase energy on leads RF, which is the input to the potentiometer and the single phase energy output of the potentiometer may be considered a zero relationship and other relationships between the two energies may be measured therefrom.

Thus, if the brushes were moved clockwise, from the assumed zero position as for example, as illustrated in potentiometer PR5, then it may be said that the relationship between the three phase input RF and the single phase output may be said to be offset from the reference zero position a certain percentage, as for example 40 degrees or 11 percent of the entire 360 potential phase difference, which potential phase difference would be for a 360 offset.

If, on the other hand, the brushes were moved counter clockwise from the zero reference, as for example as illustrated in PR6 then the single phase output may be said to be offset from the reference zero position a certain percentage, as for example, 60 degrees or 17 percent of the entire 360 potential difference.

Thus the setting of the potentiometers PR5 and PR6 may be adjusted, as desired, to any percentage offset from the established relationship between the reference input and the single phase output and potentiometer PR7 may be driven automatically to match the percentage of offset from the reference as set on one of the potentiometers PR5 or PR6 depending upon the condition of relay OS.

With relay OS deenergized, as illustrated potentiometer PR7 is driven to match PR6, as shown, and with relay OS energized so as to close contacts 84 and 86 then PR7 is driven to match PR5.

Thus a selection is made by relay OS between a plurality of offset means, of which PR5 and PR6 are two examples. However, the actual offset of the controller is determined by a single offset determining potentiometer PR7 which is driven to any selected offset by the motor RDM.

For an understanding of the manner in which PR7 is driven to match either PR5 or PR6, as selected by operation of relay OS via switch 38, it should be understood that the output of PR7 is connected to coil 91 of transformer T2. Coil 93 of transformer T2 applies an A.C. to spike pulse shaper PF2. Spike pulse shaper PF2 which is similar to the spike pulse shaper in PFl and PF3 may be in the form of an electronic circuit which upon receiving a single phase A.C. input provides a very sharp narrow spike pulse as the sine wave passes through zero in a positive direction.

The square pulse shaper in PPS may be in the form of an electronic circuit which, upon receiving a single phase A.C. input provides an output, in the form and shape of a square wave above zero, on the positive excursion of the sine wave and an output in the form and shape of a square wave below zero on the negative excursion of the sine wave.

The coincidence gate CG1 and CG2, which may be similar to each other may be in the form of an electronic circuit, including a vacuum tube having at least two grids, an anode and cathode and heater element for example. By applying the spike pulse output of spike pulse shaper PFZ to one grid of the tube, of coincidence gate CG2, for example, and the spike pulse output of spike pulse shaper PPS to the other grid of the same tube for example, the tube may be made to pass current when the two separate output spike pulses are substantially in coincidence.

When there is no coincidence between the spike pulse outputs of PFZ and PF3 as applied to coincidence gate, CG2, there is no output from CG2 and relay MS remains deenergized. Thus contact 95 of relay MS is closed and supplies a ground to the reversible motor RDM through contact 93. The motor RDM drives the potentiometer PR7 until the offset of the brushes of PR7 match the offset of the brushes of either PR or PR6, whichever potentiometer is connected across coil 90 of transformer T3. PR7 is driven by RDM, until the spike pulses occur coincidentally and are thus applied to the separate grids of a tube in CG2. CG2 provides an output thus energizing relay MS which opens contact 95 and breaks operating circuit for motor RDM to stop PR7 at an offset position corresponding to PR6 for example.

In order to drive PR7 via RDM in the closest direction square pulse shaper P1 3 and spike pulse shaper P1 2 provide outputs to coincidence gate CG3. With the spike output of PFZ applied to one grid of a two grid vacuum tube and the square wave output applied to the other grid of the same tube an output from the coincidence gate CG3 may be obtained when the spike pulse from PF2 occurs during that half of the cycle in which the square wave from PPS is positive with respect to zero. Thus with an output from CG3 relay MD may be operated thus providing absolute directional control of motor RDM as through contacts 96 and 98 of relay MD.

Thus if PR7 is to be driven clockwise to a new offset position, the spike pulse output from PFZ and the square wave output from PF3 will be applied to CG3 so that the spike pulse will occur during the positive half of the square wave and thus an output from CG3 will be provided and will energize relay MD and cause closure of contact 96 and opening of contact 98. Closure of contact 96 with closure of contact 95 would result in revolving RDM clockwise and drive PR7 clockwise. Obviously when CG3 does not provide an output as when a spike pulse is applied to CG3 during the negative half of a square wave, relay MD is held deenergized providing counterclockwise revolution of RDM .thus driving PR7 in a counterclockwise direction.

Although two potentiometer-s PR5 and PR6 are illustrated in FIG. 3 between which selection may be made for the matching of PR7, it is obvious that additional potentiometers may be added along with an additional selection relay or relays and [switching circuitry so that a selection of outputs, of similarly connected potentiometers, in excess of two, may be obtained.

The potentiometers PR1, PR2 and PR3 represent 360 potentiometers similar to PR5, PR6 or PR7 and PR1, PR2 and PR3 are connected to the variable frequency lines VF in a manner similar to that described for PR6 except that PR6 is connected to reference frequency lines RP.

The output of PR1 is connected across coil of transformer T1 via the lowermost positions of line switch banks 43 and 43a and wipers 44 and 44a with the lower position of bank 43 connected the inner ring and the lower position of bank 4301 connected to the outer ring of PR1.

With the wiper arms in the lowermost position, as illustrated, the single phase output of PR1, which is developed from the varied frequency and has a relationship thereto is applied across the coil 100 and to the spike pulse shaper P1 1, via coil 101.

Since the single phase output of PR1 bears a relationship to the three phase input from VP and the single phase output of PR7 bears a relationship to the three phase input from RF and, the three phase system VF is progressively and constantly slowly shifting in phase with respect to the three phase system RF, then the single phase output of PR1 is progressively and constantly slowly shifting in phase with respect to the single phase output of PR7. Therefore the spike pulse formed by PFI, as the single phase output of PR1 increases from zero in a positive direction, will progressively and constantly slowly shift with respect to the spike pulse output of PFZ and the two spike pulse outputs will be in phase coincidence once every complete phase shift cycle. The amount of time between coincidence of the spike pulses will normally be equal to the time between coincidence between the three phase systems VP and RF but coincidence between the spike pulses will not necessarily occur at the same instant as coincidence between the two three phase systems.

Thus with the wiper arms of the several banks of the line switches as illustrated, in the first or lowermost position, when the spike pulses from PFl applied to coincidence gate CG1 and the spike pulses from PF2 applied to coincidence gate CG1 are in coincidence, CG1 provides a positive output via contact 45 through relay PD to ground thus energizing relay PD. Energized relay PD closes its contact which completes an energizing circuit for motor magnet MM from a positive supply through motor magnet MM, contact 110 to ground.

Energized motor magnet MM notches a ratchet wheel (not shown) on a shaft (not shown) to prepare to advance the wiper arms of the several line switch banks and closes contact 107.

When the spike pulses applied to coincidence gate CG1 pass coincidence, the positive output of CG1 is halted and relay PD becomes deenergized. With relay PD deenergized, contact 110 opens and magnet MM becomes deene rgized and advances the several wiper arms to the next position in unison.

With the several wiper arms in the second position the wiper arm 121 of line switch bank provides a circuit to illuminate a yellow signal to traflic on the main street or street A of the controlled intersection while a red signal is illuminated for traffic in the secondary street or Street B of the intersection through another similar bank of switches which is not shown.

The wiper arm 123 of bank 122 provides a charging circuit for capacitor 102 from a 13+ supply through high resistance 103 and adjustable resistor 104, the second position of bank 122, arm 123 to capacitor 102 to ground.

When the charge on capacitor 102 reaches the breakdown voltage of gas tube 105, the tube 105 passes current and the energy in capacitor 102 is passed through to the relay INT to ground thus operating the relay.

Relay INT becomes energized and closes its contact 106 which causes energization of magnet MM. The motor magnet MM prepares to notch the ratchet wheel as previously described and closes contact 107. Closure of contact 107 connects a ground via such contact to the positively charged side of capacitor 102 which reduces the charge on the capacitor to below the breakdown voltage of gas tube 105 and tube 105 stops passing current. Thus relay INT becomes deenergized and contact 106 opens. When contact 106 opens the energizing circuit for magnet 13 MM becomes broken and magnet MM is deenergized causing the ratchet wheel and wiper arms to advance to the third position of the line banks.

In the third position of the line switch, the wiper arms 44 and 44a are connected to the moving contacts 46 and 48 of the SP relay respectively. The SP relay may be controlled remotely from the master as shown at or locally as desired. Thus as illustrated with split selection relay SP deenergized and moving contacts 46 and 48 in their down position, the potentiometer PR2 applies its output across the coil 100 of transformer T1. Now the output of PR2 is applied to the spike pulse shaper PFl via coil 101 of transformer T1.

It will be noticed that the brush contacting the outer ring of PR2 is displaced more clockwise than the brush contacting the outer ring of PR1, thus coincidence between the spike pulses formed from the output of PR7 and from the output of PR2 will occur somewhat later in the phase shift cycle than coincidence between the spike pulses formed from the output of PR7 and from the output of PR1.

Coincidence between the spike pulses of PF1 from PR-2 and PF2 from PR7 in coincidence gate CG1 provides a positive output through contact to energize relay PD and causes advancement of the wiper arms as previously explained, to the fourth position of the several banks of line switches.

In the third position arm 121 of bank 120 provides a green signal, BG, for secondary or B street trafiic and a red signal (not shown) is displayed to main street traflic at the controlled intersection.

With the several wiper arms advanced to the fourth position the arm 123 connects B-lsupply through high resistance 103 and adjustable resistance 108 through the fourth position of line switch bank 122 through wiper 123 to capacitor 102 to ground thus resulting in advance of the wiper arms as previously described.

With the wiper arms in the fourth position arm 121 provides a circuit to illuminate a yellow signal BY, to vehicle trafiic on the secondary street, B street, while a red signal (not shown) is displayed to vehicle trafiic on the main street.

As the several wiper arms advance off the fourth positions another set of wiper arm make contact with the first position of the individual banks of line switches and the wiper arms 44 and 44a connect across the output of po tentiometer PR1 and the cycle of operations is repeated.

The foregoing description assumes that the switch 130 is open with relay PR deenergized:

Standby operation of the local controller Let it be assumed that the switch 130 is closed so that relay PR is energized. Contact 41 would be open and contact 53 would be closed. The ground supply to reversible motor RDM would be opened and motor RDM would stop and a ground supply would be completed to the STANDBY controller via contact 53. Contact 45 would open to disconnect the output of coincidence gate CG1 from the relay PD and contact 54 would close to connect the relay PD to the standby controller 50. The PD relay, as will appear, hereinafter, controls the operation of the stepping switch of the local controller. As stated above, this relay can be controlled by either the standby controller or the coincidence gate of the local controller. Which of these two circuits controls the PD relay is determined by the energization or de-energization of the PR relay which in turn is controlled by a switch 130.

Operation of the relay PR is here illustrated as by closure of a manual switch 130. However, the switch may be either remotely or locally controlled or the relay PR may be automatically controlled, as for example, if the switch 130 were contacts of a relay which relay was operated upon a certain occurrence as desired.

Let it be assumed that relay PR is energized by closure of switch 130 to ground and that contacts 41 and 45 are 14 open and contacts 53 and 54 are closed. Also, that the several wiper arms are in the lowermost or first position so that a green signal (AG) is displayed to traffic on the main street, for example and that a red signal (not shown) is displayed to traffic on the secondary street, for example.

Referring back to FIG. 2, with the closure of contact 53, ground is supplied to the standby motor 156 to drive the brushes B1, B2, B3 and B4 clockwise, with brush B1 making contact with the individual segments of commutator ring 152 as the brush is advanced clockwise around the ring of segments.

When the brush B1 makes contact with the segment of commutator ring 152 corresponding and connected to the segment of ring 151 with which brush 162 is in contact, a circuit is completed from power through wiper 56, the first contact position of bank 55, wire 170, brush 162, the segment of ring 151, to the corresponding segment of commutator ring 152 via printed circuit conductor connection, brush B1, brush B2, ring 153, lead 167, contact 54, the coil of relay PD to ground. This last described circuit causes energization of relay PD which causes closure of contact shown in FIG. 3.

Closure of contact 110 provides an energizing circuit for motor magnet MM which prepares to advance the wipers of the several line switch banks. Continued rotation of the brushes B1, B2, B3 and B4 moves the brush B1 off the segment of commutator ring 152 of the above described circuit to open the energizing circuit for the relay PD. Deenergized, the relay PD opens contact 110 which causes MM to become deenergized and advance the wiper arms of the line switch banks to the next or second position.

In the second position of the line switch banks, the green signal AG is extinguished and a yellow signal AY is illuminated to traffic on the main street, for example, while a red signal is maintained illuminated to trafiic on the secondary street all as previously described. Also in the second position the interval is timed as previously described, resulting in energization of relay INT and subsequent energization of motor magnet MM. This interval terminates with deenergization of MM and the advance of the wiper arms of the several banks of the line switch in unison to the next or third position.

In the third position of the line switch banks as previously described, a green signal is illuminated and displayed to traffic on the secondary street while the red signal having been so displayed is extinguished. The yellow signal is also extinguished and a red signal is illuminated and displayed to traffic in the main street.

Rotation of the brushes B1, B2, B3 and B4 continues and when the brush B1 connects with the segment on commutator segment ring 152 corresponding to the segment of ring 151 to which adjustable brush 163 is connected, a circuit is completed from power through wiper 56, the third contact position of bank 55, wire 171, adjustable brush 163, the segment of ring 151, to the corresponding segment of commutator ring 152 via printed circuit conductor connection, brush B1, brush B2, ring 153, lead 167, contact 54, the coil of relay PD to ground. This last described circuit causes energization of relay PD which causes closure of contact 110. Closure of contact 110 provides an energization circuit for motor magnet MM which prepares to advance the wipers of the several line switch banks. Continued rotation of the brushes B1, B2, B3 and B4 moves the brush B1 off the segment of commutator ring 152 of the last described circuit to open the energizing circuit for the relay PD. The relay PD becomes deenergized and opens its contact 110 which opens the energizing circuit and deenergizes motor magnet MM thereby advancing the wiper arms of the several banks of line switches in unison to the fourth position.

With the wiper arms in the fourth position of the line switch banks the green signal (BG) is extinguished and 15 a yellow signal (BY) is illuminated and displayed to traflic on the secondary street while the red signal displayed to tratfic on the main street is maintained.

The interval is now timed through the fourth position of line switch bank 122 as previously described and the wiper arms are advanced off of the fourth position and on to the first position.

Thus operations of the signal sequence switch by the standby controller, in cooperation with static timing of the local controller has been described.

It should be noted that the standby controller as illustrated in FIGS. 2 and 4 is a cyclic time controller in itself since motor 156 is geared for a slow speed. Such a time controller in cooperation with the motor magnet could be a local traffic controller in itself rather than as a standby controller for a local traffic controller. Several embodiments could be devised by those skilled in the art. For example the first and third steps of the controller could be controlled by the setting of brushes 162 and 163 while the second and fourth steps could be controlled by capacitor timing circuits as in FIGURE 3 with 102 and 105 etc. Alternatively, four brushes similar to 162 and 163 could be utilized to control four steps of the controller, for example. Such a modification as referred to above will be described hereinafter in reference to FIG- URES 11 and 12.

Also, while a preferred particular configuration of contacts on the printed circuit has been described in reference to FIG. 3 and will be described more fully in reference to FIG. 4, other modifications are contemplated within the scope of this invention. For example, the contacts of 151 may be on one side of an insulating board and the contacts of 152 could be directly behind them on the other side of the board or alternatively the contacts of 151 could be positioned concentrically within or without the circle of contacts 152. Printed or other circuit connections may be provided between the contacts of 151 and 152 by means known in the art.

For example, printed circuit segments 151 on one side of an insulation panel may have eyelets, pins or rivets through each segment from said one side of the insulating panel to the other. The pins on the other side would thereby serve as the commutator segments 152. Alternatively, pins may extend through the segments of 152. However, these alternative structures would be more expensive and less reliable than the preferred structure shown in FIG. 4, in addition to other disadvantages with respect to other cooperating members.

Referring to FIG. 4, the preferred pattern of the printed circuit is illustrated with the printed circuit electrical contact segments 151, in black, arranged in the form of a wheel. Each of the segments of 151 is connected to a corresponding electrical contact segment of the segmented commutator 152. Contact ring 153 is connected via lead 167 to a terminal to which a lead to contact 54 is connected. One end of lead 170 is connected to position 1 of bank 55 while the other end of lead 170 is connected to a spring contact 204 on the reverse side of the printed circuit panel as more clearly seen in FIG. 6 and FIG. 7.

As will be explained below in connection with FIGS. 6 and 7 the spring contacts 204 and 213 cooperate with further elements to connect with brushes 162 and 163 respectively.

One end of lead 171 is connected to position 3 of bank 55 while the other end of lead 171 is connected to a spring contact 213 on the reverse side of the printed circuit panel as more clearly seen in FIG. 6 and FIG. 7.

Terminal 172, connected to split ring 155 is connected via a lead on the reverse side of the panel to the segment 173 of selector switch 165 while the segment 173 is externally connected to motor 156. Terminal 174 is connected to ring 154 and terminal 174 is connected to a common ground or negative terminal.

Printed circuit leads 1 and 176 provide leads for additional spring contacts on the reverse side in the event that three or four adjustable brushes are desired.

Assemblies 180 through are six printed segments for three position selector switches.

Referring to FIG. 5 and FIG. 6 jointly, FIG. 5 is a face or front view of a control and indicating panel for the standby control mechanism, and for certain selector and indicating features of the normal coordinated control mechanism, in the preferred form while FIG. 6 is a partly cutout side view of the panel and associated mechanism in back of the panel.

Directing attention to the bottom of the FIGS. 5 and 6, a hinge 188 is illustrated which permits the face panel 186 to open, pivoting forward on the hinge for easy access to the interior components. The large head screws 189 and 189a fit through the face plate 186, and thread into posts 190 which are mounted in the back plate 191.

By loosening or removing both large head screws 189 and 189a the face panel 186 may fall forward, pivoting on the hinge 188.

The face panel is separated into two sections, Standby Operation and Coordinated Operation; in the center of the standby operation section are two dials 192 and 193 with dial 192 attached to a hollow shaft 194. The hollow shaft 194 is fitted with a spacing washer 195 so that the dial 192 is held away from the face panel. A hole in the face panel permits insertion of the hollow shaft 194 through the face panel and a hole in the center of the printed circuit segments 151 permits the hollow shaft 194 to extend through and beyond the printed circuit board 196. The printed circuit board 196 is mounted separated from the back of the face panel 186 by spacing bushings as for example 197 that are threaded to receive mounting screws 198 (or 198a) and 199. The shaft 194 extends beyond the printed circuit panel 196, and a disc 201 is fitted thereon, with an annular metallic conductor ring 202 fitted on the surface of the disc, and with brush 162 connected to the metallic conductor ring and the latter being insulated from the shaft 194.

An exploded view of this assembly is presented in FIG. 7 which shows more clearly the individual components of the assembly.

The disc 201 is fitted on to the shaft 194 so that the disc 201 will rotate when the shaft 194 is rotated by rotation of the dial 192.

The brush 162 makes contact with one of the segments of the segmented printed circuit 151 as selected by the setting of adjusting knob 192, but is preferably of sufficient width to bridge adjacent segments if accidentally set on a line between segments.

A spring conductor 204 connects with the printed circuit lead 170, the spring conductor holding a brush 205 against the metallic annular ring 202 on the face of disc 201, the brush 205 slidably extending through a close clearance hole 251 in the panel 196.

Adjusting dial or knob 193 is connected to a shaft 206 which is fitted into the hollow section of shaft 194. The dial 193 is held away from dial 192 by a spacing washer 209.

The shaft 206 extends beyond the end of the hollow shaft 194 and is fitted with an insulating spacing washer 210 and a disc 211. A face view of disc 211 is illustrated in FIG. 8 where it is shown that the center hole is shaped to cooperate with a flatted part 206 of shaft 206, and the face of the disc 211 includes an annular metallic conductor 212 and brush 163 connected thereto and projecting therefrom.

A spring conductor 213 connects with the printed circuit lead 171 and holds a brush 214 against the annular metallic conductor 212. The brush 214 is slidably guided by insulating bushing 214, which is pressed into a hole 250 through panel 196 to insulate the brush 214 from segment 151. The adjustable brush 163 makes contact with one segment of the printed circuit segments 151, and is also preferably of slightly bridging type.

An insulating washer 215 is fitted between the disc 211 and a lock washer 216, and a nut 217 threads onto the shaft 206 thereby holding the components in place. A spacing bushing 218 keeps the printed circuit board 196 away from the face panel 186, and an insulated spacer 219 keeps the disc 201 away from the other side of the printed circuit board 196, the top of bushing 218 being flatted to provide clearance for the end of spring 204.

In FIG. 6 and FIG. 7 the spacing of brushes 205 and 214 has been increased somewhat for clarity, as compared with the spacing and angular position of the corresponding holes 251 and 250 in the printed circuit board 196 as shown in FIG. 4.

As is noted above the adjustable dials and brush assemblies are individually rotatable by the use of concentric shafts 266 and 194, one of which shafts is preferably solid. It will be understood that additional such adjustable means may be provided by additional dials and concentric shafts and brush assemblies etc. The printed circuit connections at 175 and 176 provide two additional circuit connections for such further adjustable means. These additional brushes might be used to provide additional control as for example in a three phase stand-by controller or may be used to control the yellow periods in a two phase controller or may be used to provide time intervals for control of traffic signals so that the printed circuit assembly itself forms a traffic controller.

It should be understood that the printed circuit illustrated in FIG. 4 is on the right hand side of the board 196 as shown in FIG. 6 and FIG. 7 where the adjustable brushes 162 and 163 make contact. Electrical connection between the spring contacts 264 and 213 which are on the reverse side of the board 196 and printed circuit leads 170 and 171 respectively is made through metal screws and nuts which hold these spring contacts.

As seen in FIG. scale marking around the dials 192 and 193 cooperate with small triangles 252, 253 or index marking on the dials to indicate the setting of the adjustable brushes 162 and 163.

The knob 220 on the face panel 186 in FIG. 5 does not appear on FIG. 6 since FIG. 6 is a partial cutaway view along the broken line 221. However the knob 220 is attached to a rotary shaft extending through the panels 186 and 196, the shaft being fitted with a bridging connection for selectably connecting any one of the upper contacts of the switch assembly 165 to the lower contact 173. This switch assembly is illustrated in FIG. 5.

Mounted on back plate 191 is a motor 222 which drives a gear 223 which drives a stepdown gear 224 as shown in FIGURE 9. The combination of the speed of rotation of the motor 222 and the size of the gears 223 and 224 rotates the shaft 225 at a desired speed. Shaft 225 is generally round for reception in bearing 266. However one end of shaft 225 is square at 265 for cooperation with spring 226 as will appear below. A C washer 267 is provided to cooperate with the groove on 225 and 268 is a spacing washer.

A coupling spring 226 in the form of a bent spring metal strip is employed between shaft 225 and a shaft 229 which is driven slowly, of the order of one revolution every 60 seconds, for example. The shaft 229 rotates in 1a bushing 257 which is mounted on the insulating board 196 upon which the circuits of FIG. 4 are printed. On the other end of shaft 229 is a disc 239 on which is marked a series of numbers in a circular arrangement, part of which may be seen through hole 258 in front panel 186 on FIG. 5. These numbers divide the circle into parts of one hundred percent so that the numbers will appear through the hole 258 in the front panel to cooperate with an index mark on the panel as shown in FIG. 5 to show the position of brushes B1, B2, B3 and B4 in their rotation cycle and thus indicate which of the circle of segments 152 and thus also of segments 151 is energized at any instant of time.

This disc 230 indicates the position of the brushes B1, B2, B3 and B4 which are supported on the arm 231 which is attached to or integral with shaft 229. Brushes are mounted at an angle and are connected in parts by extensions 232, 233. A threaded hole 266 (not shown) is provided on shaft 229 for cooperation with screw 259 and spacer 261 for frictionally holding the disc 230 in cooperation with shaft 229.

The coupling spring 226 has a square hole 256 for engagement with shaft 225 and two holes 255 for engagement with shaft 229 and one lip portion 226' for engagement with one side of arm 231. FIG. 9A more clearly shows this coupling spring in detail.

A C washer 261 is provided to cooperate with the groove 262 on shaft 229 so that the brush assembly is retained by the panel 196 for rotation therein. Insulating spacing washers 263, 264 space the printed circuit element on panel 196 from the wide portion of bushing 257 to prevent that bushing from shorting the connection areas 172 and 174 of the printed circuit (shown in FIGURE 4).

The brushes B1, B2, B3 and B4 are rotated by the shaft 229 and contact the commutator segments 152, the ring 153, the ring 154 and the interrupted ring respectively. An exploded view of these components is illustrated in FIG. 9 and FIG. 10 shows a face view of the arm 231 which is mounted on the shaft 229. The arm carries the brushes B1, B2, B3 and B4. The brushes B1 and B2 are joined at 232 and brushes B3 and B4 are joined at 233.

In FIG. 6 the motor RDM, also represented in FIG. 3, is mounted on the back plate 191 and drives a potentiometer PR7.

A drive gear 237 rotates a gear 269 (teeth not shown) on which there is an indicator plate 238 with an arrow which maybe used to indicate the position of the contact arm of the potentiometer relative to a known or zero position.

Individual traffic signal split selector switches have five knobs 240, 241, 242, 243, and 244 and a blank 245 for a sixth knob are indicated on the face plate with knob 242 illustrated on a shaft 246 on which is connected the adjusted jumper switch contact 247 for providing shorting contact on an individual switch.

The jumper contact 247 may, for example, be associated with printed circuit switch assembly (FIGURE 4).

FIG. 11 illustrates schematically another form of printed circuit apparatus which is particularly adapted as an independent local traffic timer or controller. While in some aspects the apparatus of FIG. 11 is similar to the apparatus of FIGS. 2 and 4, FIG. 11 in addition provides four adjustable brushes (rather than two) so that traflic signals may be controlled at four percentage points in the trafiic signal cycle. FIG. 12 illustrates schematically a capacitive timing circuit and associated apparatus which may cooperate with the embodiment of FIG. 11 in which only two such brushes are utilized so that while the traflic signals are still controlled at four points within the traffic signal cycle, the two green periods may be determined on a percentage basis and the two yellow periods may be determined on a fixed time basis.

The embodiment of FIG. 11 requires fewer elements than the embodiment of FIGS. 2 and 3 since the printed circuit apparatus of FIG. 11 is not required to cooperate with another controller.

In FIGS. 2 and 3, both the standby and normal timer utilized the same motor magnet MM and signal sequence switch. Therefore the PD and PR relays were utilized to distinguish which of these timers was to be effective.

It is clear that where the printed circuit timer is intended for independent operation as a local controller,

19 as in FIGS. 11 and 12, that the PD and PR relays may be omitted. Hence only the motor magnet MM is shown in FIG. 11 and this magnet when stepped may control banks of switches 55 and 120 in a similar manner as in FIGS. 2 and 3.

In describing FIGS. 11 and 12, the same numerals are used as in FIGS. 2 and 3 for similar elements.

Motor means 156 is shown for driving brushes B1 and B2. The motor may be connected to a source of power for continuous rotation or may be controlled by a switch 165 which may be remotely or locally controlled as desired.

Two circular configurations of contacts 151 and 152 are shown as in FIG. 2 with the exception that four brushes rather than two are shown at 162, 162', 163 and 163'. These four brushes determine when the traflic signals switch from A-green to A-yellow, A-yellow to B-green, B-green to B-yellow and B-yellow back to A- green, respectively for example, and are manually adjustable as described hereinbefore.

The lamp switching system is shown in simplified form for convenience of illustration. It will be obvious to those skilled in the art that additional banks of switches may be utilized if desired to provide for independent red and green signal circuits for example.

As the motor rotates, the motor magnet MM is periodically energized to step the line switches 120 and 55 thereby switching the trafiic signals at time intervals determined by the setting of the four brushes and the speed of the motor. The circuit for MM is from ground (minus) through MM to 153, through B2 and B1 and through the segmented electrical contacts of 152 and 151 as interconnected by printed wires such as 158, 159 or 160, etc., to one of the four brushes 162, 162, 163, 163' as energized through the switch 55. For example, if the switch contact banks are in their first position, as shown, the A-green and B-red traffic signals are energized through switch bank 120. As the motor rotates brushes B1 and B2 counterclockwise, a certain segmented electrical contact of 152 (connected to 158 for example) will be connected to the positive source of switch bank 55 through the brush 162. Thus MM will be energized to prepare arms 56 and 121 to step to their second position as the brushes leave the said segmented contact thereby energizing the A-yellow signal. Similarly, as the motor continues rotation, another certain segmented contact on 152 will be energized as determined by brush 162 to again energize MM which will step the wiper arms 56 and 121 to thereby energize the B-green signal as soon as brush B1 leaves said certain segment of 152. Subsequently B-yellow will be energized at a time determined by adjustable brush 163, and finally there will be a return to A-green as determined by adjustable brush 163' to complete a trafiic signal cycle.

The length of the traflic signal cycle of the embodiment of FIGURE 11 will be determined by the speed of the motor means. Numerous modifications of this signal cycle may be obtained by methods known to those skilled in the art. For example, gears of varying size may be used as well as a variable frequency source for driving the motor.

Since the operation of the trafiic signals is controlled by the setting of the adjustable brushes 162, etc., and rotation of brushes B1 and B2 by the motor means, it is clear that if one rotation of the brushes B1 and B2 is considered a cycle or 100%, then the operation of the trafiic signals occurs at selected percentages of the signal cycle as determined by the setting of the adjustable brushes. Hence concentric calibrated adjustment and indicating means may be utilized with such a controller as has been disclosed hereinbefore as concentric knobs 192 and 193. The knobs may be connected to their associated brushes through concentric tubes. The brushes or dials may be provided with means to maintain a predetermined sequence between the brushes thereby maintaining a desired sequence of trafi'ic signals. Such means are known by those skilled in the art of dial controls.

It will be appreciated that the traffic signals of FIG. 11, as determined by the calibrated adjustable brush controls, are switched at time intervals which are percentages of the signal cycle. Therefore, if the signal cycle is varied in length, all periods would vary proportionately. If cycle length were increased, this would provide more yellow time than necessary. Hence it is desirable to permit such yellow periods for only a time which does not vary with variations in cycle length. A capacitance timing circuit (FIG. 12) will perform this function While still being capable of adjustment. FIG. 12 illustrates that if only two brushes 162 and 163 are used in FIG. 11 (first and third position of 55) to terminate the A- green and B-green signals of 120, and a third bank of contacts 122 is linked to MM, a capacitor 102 may be charged from the positive source through resistor 104 in the second position of 122 through wiper arm 123 and capacitor 102 to ground (minus). After an R-C time interval, gas tube 105 will fire to energize the INT relay to close contact 106 and energize the motor magnet to step the associated wiper arms of the switch banks to their third position. In the third position of the wipers, the adjustable brush 162 of FIGURE 11 would again assume control to energize the motor magnet and step the line switches to their fourth position.

In a similar manner, in the fourth position of the line switches, capacitor 102 is again charged to energize MM after a second R-C time to step the line switches back to their first position where brush 162 will now be effective to complete a trafiic signal cycle.

Resistor 104 and 108 are shown as being adjustable to adjust the yellow time interval.

Each time that motor magnet MM becomes energized, it closes contacts 107 to short circuit capacitor 102 and thereby reduce its charge to zero, ready for the next interval to be timed.

The embodiment of FIGS. 11 and 12 may of course have elements subtracted from or added thereto as is known by those skilled in the art. For example, the homing ring 155 of FIG. 2 may be utilized to provide coordination of such printed circuit controllers by establishing a rest or stop position in its cycle. The gap in such a ring would preferably be oriented with respect to brushes 162 and 163 to initiate control of such controllers in an A-green or B-green period.

Resynchronizing means may be preferably utilized to initiate control of a system of such controllers by driving all of the controllers from the gap or its electrical equiva lent.

Also it will be apparent that bank 55 is not required for the printed circuit controller of this invention and that brushes 162, 162", 163, 163 may be directly connected to a source of power or ground. However, in the preferred embodiment supplying power to the brushes through bank 55, permits each brush to be energized only at its proper time in synchronism with the traffic signal cycle.

It will be apparent to those skilled in the art that a group of electrically interlocked relays could be substituted for stepping switch banks and 55, and operating magnet MM, connected in such a way that each successive closure of the circuit which energized MM in the embodiment shown in FIG. 11 would, instead, send a power pulse through the chain of relay contacts to energize or deenergize one or more relays, so that other contacts on these relays would open or close the circuits now shown as controlled by banks 120 and 55.

Advantage of homing control As has been disclosed above (FIG. 2) the homing control permits motor 156 of the standby timer to drive the brushes to a zero reference position when it is not effective for controlling the traffic signals. The circuit is 21 from ground (minus) through B3 and B4 to ring 155 so that motor 156 is driven to a reference point determined by the gap in the ring.

For example in FIGURE 1 if switch 53 and 54 had been closed to energize the standby controller, when switch 41 and 45 is closed to energize the normal timer, the standby controller will always return to its zero position independent of the position of the standby controller when the normal controller is thereby energized and therefore the standby controller is again ready to assume control at the next failure.

This characteristic is of importance independent of whether the printed circuit controller is utilized as an independent local controller or as a standby unit for a local controller. The reason for this is that as a standby controller, the homing control assures that when the standby units are called into operation (as by failure of the master or interconnecting wires, for example) all the standby units will start at one and the same reference point. However, when the printed circuit controllers are used as individual local controllers, this homing ring 155 (FIG- URE 2) in cooperation with switch 165 may permit setting up a group of such printed circuit controllers as a progressive or simultaneous trafiic control system. For example, if individual such printed circuit controllers are arranged at a series of intersections, each controller would home to its zero position. Switch 165 (FIGURE 2) is capable, when operated, of driving the motor 156 from its rest position or stopping the motor as desired. Assuming that each motor is geared to provide a sixty (60) second cycle (although it may be 50 or 40 seconds, etc.), switch 165 would be manually operated to start the controller. Subsequently, at a time later by some multiple of sixty seconds (or 50 or 40 etc.), the switch 165 in the second controller at the next intersection will be operated to start its motor. Subsequently all the remaining controllers will be started in the same manner so that all the controllers are operating and have a common reference or zero point. Traffic signal switching will then occur at each local controller as determined by the setting of adjustable brushes 162, 163 and knobs 192 and 193 with respect to by reference point so that adjustment of the knobs determines the desired system.

While many of the details of the invention as disclosed will be obvious to those skilled in the art in the interest of additional clarity it should be noted in FIG. 4 that the contrasting surfaces of black dots on a white background and vice versa indicate centers of clearance holes for receipt of certain shafts or for making electrical connection from one side of the printed circuit board to the other or the like. Also, holes shown at the ends of the lower actuated section in the printed circuit board associated with switch 189-185 are for detents to limit rotation of the rotor contact of such switches.

In addition, while preferred forms of the apparatus and its modifications have been disclosed, it will be obvious to those skilled in the art upon reading of this disclosure that numerous variations may be devised within the scope of this invention; for example, a terminal of a source of power may be directly connected to one or more of selected segments of commutator 152 such as by wires having terminal lugs or plugs for cooperation with selected segments. Such an arrangement would still require the scanning motor and would retain some measure of adjustability in contrast with a direct soldering connection of power to these segments.

Also the brushes B1 and B2 or B3 and B4 may supply power to the printed circuit segments by scanning rather than derive power as in the preferred embodiment,

In addition it is understood that the source of power has two terminals shown as plus or minus in a circle. The minus is generally a ground lead but could obviously be just a common terminal or any other connection to a source of power as is well known.

The above suggested modifications while providing simplicity in some respects, have decided disadvantages over the preferred embodiments in that they are more expensive and difficult to manufacture or lack the easily adjustable characteristics of this invention as will be appreciated by those skilled in the art.

Printed circuits as used herein are well known in the art as encompassing several methods of making electrical contacts and associated circuits on an insulated base member.

Etching, plating and painting are several such methods. For a more complete discussion of printed circuit techniques and methods, reference is made to the Proceedings of the Symposium on Printed Circuits at the University of Pennsylvania copyrighted in 1955 by Engineering Publishers.

While the above invention has been described with reference to its preferred form, it will be obvious that equivalent means are contemplated within the scope of this invention so that the scope of this invention is therefore embodied in the following claims.

I claim:

1. In a traffic signal controller, a cyclic switching device having a multiplicity of positions through which it is adapted to be advanced for operating a trafiic signal through a cycle including a first go signal operating position and a second go signal operating position through which it is adapted to be advanced in response to respective electrical control signals,

first cyclic timing means for providing respective electrical control signals spaced in a time cycle for normally advancing said cyclic switching device in the respective go positions when operatively connected to said cyclic switching device therefor,

standby second cyclic timing means for providing respective electrical control signals at two respective points in a time cycle for advancing said cyclic switching means in said respective positions when operatively connected to said cyclic switching device therefor and including means for adjustably setting the time positions of said respective points for the time of advance of the cyclic switching means individually for the respective go positions with respect to a desired reference position in the cycle of said second cyclic timing means,

switching means having first and second respective alternative switching positions, said switching means being operative for immediate switching from either of its positions to the other at any time desired in random relation to said reference position,

.rneans operated by said switching means in its first switching position for so operatively connecting only said first cyclic timing means to said cyclic switching device,

means operated by said switching means in said second switching position for so operatively connecting only said second cyclic timing means to said cyclic switching device, means operated by said switching means in its second switching position for operating said second cyclic timing means through its cycle including said reference position,

means made effective by said switching means in its first switching position for operating said second cyclic timing means to stop at said reference position.

2. A combination as in claim 1 and in which said means for operating said second cyclic timing means to stop at said reference position includes motor means for operating said second cyclic timing means in its cycle,

an annular fixed electrical contact with a gap therein at said reference position,

rotary brush means rotated by said motor means for traversing said annular contact,

circuit means for supplying power via said annular con tact and said rotary brush to operate said motor means,

and in which said means for operating said second cyclic timing means through its cycle including said reference position includes switch contacts operated by said switching means in its said second position for effectively shunting said gap in said annular contact to apply power directly to said motor means.

3. A combination as in claim 1 in which the means in the second cyclic timing means for adjustably setting the time of advance individually for the respective go positions with respect to a desired reference position in its cycle includes at least two electrical contact brushes individually manually adjustable with respect to said refer ence position, a terminal for connection to a source of power and means connecting said brushes to said terminal for supplying power to the cyclic switching device in two particular portions of the cycle of said second cyclic timing means as so adjusted thereby providing advance of the traffic signals at time intervals in dependence upon the adjustable means.

4. A combination as in claim 3 which further includes two manually adjustable concentric knobs each of which is individually connected to one of the brush contact elements so that each contact element and its associated knob may be individually rotated to supply power to the cyclic switching device only in the two individual portions of the cycle of the second cyclic timing means.

5. A combination as in claim 1 in which the second cyclic timing means further includes an insulating board having a plurality of electrical contacts printed thereon with respect to a reference point coordinated with said reference position; and in which certain ones of said plurality of contacts, as controlled by said adjustable setting means, are connected to a source of power; and means for scanning said plurality of contacts by connection therewith in sequence for deriving power from said certain contacts for advancing the cyclic switching means at time intervals in dependence upon the speed of the motor and the time positions set by said adjustable setting means.

6. A combination as in claim 5 in which the plurality of contacts includes two circular configurations of contact elements in which the individual contacts in one circle are electrically connected to individual contacts in the other circle, adjusting knobs and electrical contact brushes being rotatable thereby on one circle of contacts for supplying power directly to particular contacts on said one circle and thereby to particular contacts on the other circle as so interconnected, motor driven brush contact means for deriving power from said particular contacts on said other circle for advancing the cyclic switch device at corresponding particular points with respect to the reference point as the motor rotates.

7. A trafiic controller for controlling a traffic signal at intersecting traflic lanes comprising,

an insulating base member,

a plurality of electrical contact elements printed on said insulated base member and separated from each other to form a plurality of contact positions in a substantially circular array,

means for connecting a source of power selectively to at least two particular such contact elements,

step-by-step trafiic signal sequence switch means for operating stop and go signals in a cycle including at least two go signal periods in respective steps at the intersecting traffic lanes, said sequence switch means including driving means for advancing said sequence switch means from one step to another in its cycle in response to application of power to said driving means,

scanning means including a motor and contact brushes rotated thereby for sequentially scanning the circular configuration of contact elements, one of said brushes being electrically connected to said driving means of said sequence switch means, whereby said driving means receives power to advance said sequence switch to initiate a change of traffic signals as the said particular contacts are scanned to provide a traffic signal cycle in a single scanning cycle of the brushes.

8. A combination as in claim '7 in which the means for connecting power to particular contact elements includes a second plurality of contact elements printed on said insulating board, spaced from the first group of contacts and in which each individual element of the second plurality of contacts is connected by a printed wire to a corresponding individual contact element of the first plurality, at least two adjustable .brush means concentrically mounted on rotary dial type knobs and individually adjustable for providing power to at least two contact elements of the second group of contacts, whereby two contacts of the first group are energized through the printed wires and the traffic sequence switch means is energized at least twice, in dependence upon the adjustable setting of the brush means, within one cycle of the signals.

9. A combination as in claim 7 further including preset resistance-capacitance timing means for controlling said traflic signal sequence switch means when said scanning means is not scanning said particular contacts so that said traffic signal sequence switch is operated to complete a cycle in dependence upon both said preset resistance-capacitance timing means and the adjustment of the brushes.

10. A traffic control system for controlling a plurality of intersections including trafiic controllers individual to each intersection and in which each controller includes a signal sequence switch for operating traflrc signals,

an insulating board having a plurality of electrical conducting contacts printed thereon, one of said contacts being substantially annular and having a gap therein,

a motor and electrical brush contacts rotated thereby across said printed contacts to sequentially scan each contact,

terminal means for connection to a source of power,

circuit means connecting said motor through a brush contact via said one annular contact to the power terminal so that the brushes driven by the motor rotate to the gap and stop therein to define a zero reference point for each of said controllers,

means for selectively connecting power to any two other contacts in a ring of individual said printed contacts correlated to said reference point so that the particular other contacts which are so energized in each controller are in selected positions olfset with respect to the zero reference point as desired,

switch means for connecting power to said motor in parallel with said circuit means so that the motor is driven from the gap for normal rotation,

means connecting power to the signal sequence switch through said two selected contacts as the motor operated brushes scan them to advance said sequence switch in its sequence so that the signal sequence switch of each controller is advanced at time intervals determined by the selected offset positions of said energized contact elements from the common reference zero position so that each controller can have independent adjustable offset positions with respect to a common reference position for operating its traffic signal as desired.

11. A traflic controller including signal sequence switch means for providing a cycle of control of traffic signals,

a reference phase signal,

olfset and split phase control means adjustably positioned and varying in phase with respect to said reference phase to provide offset and split phase signals respectively,

phase coincidence means for comparing the reference phase signal with the offset and split phase signals respectively for deriving first and second control outputs in response to phase coincidence of the offset and split phase signals with the reference phase signal respectively,

a standby cyclic timer for deriving third and fourth control outputs, said standby timer including a printed circuit panel having a plurality of contacts printed thereon in a circular configuration,

a motor and associated contact brushes rotated thereby for scanning said contacts by connecting with said contacts in sequence and means for selectively connecting power to two of said contacts in desired positions in said circular configuration so that said third and fourth signals are derived as said brushes scan said selected two contacts respectively;

and means controlled by either the first and second control outputs or the third and fourth control outputs when coupled thereto for controlling said signal sequence switch for advancing the latter in its cycle, and

switching means having a first position for coupling only said first and second control outputs to said sequence switch control means and having a second positon for coupling only said third and fourth control outputs to said sequence switch control means for so advancing said sequence switch.

12. A traffic controller as in claim 11 and in which the standby timer includes further fixed contacts on said panel and further contact brushes rotated by said motor for scanning said further contacts for driving said motor for rotating said brush contacts to stop in a reference rest position when said switching means is in its first position, and

means for driving said motor to rotate said brushes from said reference rest position to provide said third signal and said fourth signal and sequence for so advancing said sequence switch when said switching means is in its second position.

13. The combination as in claim 11 further including resistance-capacitance timing circuits, and circuit means for controlling the signal sequence switch means alternately by the resistance-capacitance timing circuits and either the first and second or the third and fourth control outputs whereby the initiation of switching of certain trafiic signals will be alternately controlled on a preset time basis and on a percentage of the trafiic cycle basis as determined either by phase coincidence or by the setting of the printed circuit contacts.

14. The combination as in claim 11 in which the adjustable means includes two concentric adjustably rotatable knob members which are individually connected to contact brush members for supply-ing power to the selected two of said contacts.

15. A traflic controller comprising normal and standby cyclic timing means for producing periodic electrical output signals,

traific signal sequence switch means for controlling traffic signals in response to the outputs of either the normal or standby cyclic timing means,

means for making effective either the normal or standby timing means selectively for providing said outputs to said sequence switch means;

said normal cyclic timing means including two signal sources of electrical signals, one of which electrical signals slowly varies in phase with respect to the other, phase coincidence means for comparing the phase of said two electrical signals to produce said electrical outputs at time intervals determined by phase coincidence of said electrical signals, said standby timing means having an insulating board with a first plurality of electrical contacts printed thereon in a circular configuration, a second group of contacts also printed thereon, and printed circuit contacts interconnecting individual contacts of the first plurality to individual contacts of the second plurality; terminal means for connection to a source of power, adjustable calibrated dial members concentrically mounted and adapted to have individual electrical contact brushes connected thereon, motor means having a motor and rotatable second electrical brushes driven thereby for scanning said first plurality of contacts, circuit means for connecting said terminal to said first brushes for supplying power via said first brushes to the second plurality of contacts as so adjusted and through the interconnections to certain individual contacts of said plurality of contacts so that power is derived from said contacts through said brushes to control the traffic signal sequence switch means as certain contacts are scanned to provide a time cycle of said standby cyclic timing means, said printed circuit also including,

further contact means for driving said motor means of said standby timing means to a reference point in said time cycle when said normal timer means is made so effective, and visible indicator means coupled to said motor means to be rotated thereby with said second brushes for indicating the position of said standby cyclic timing means within its cycle. 16. A trafiic controller for trafiic signals including cyclic switch means for providing a tralfic signal control cycle in response to respective control signals, cyclic timing means providing at least two control signals for controlling said cyclic switch means within a single cycle of said cyclic timing means for cyclic operation of said trafiic signal, said cyclic timing means including a printed circuit panel having a plurality of contacts arranged in a circular configuration and motor means having brush contacts for scanning the plurality of contacts, in which one rotation of the brushes determines a single cycle and in which the scanning of the brush contacts will derive said at least twocontrol signals from said plurality of contacts within a single cycle of the cyclic timing means, indicator means comprising a rotary dial calibrated in percent of its traffic signal timing cycle and mechanically coupled to said motor to be rotated thereby for continuously indicating at said controller the percentage position of the traflic signal timing cycle that the cyclic timing means is in, said cyclic timing means also including adjustable dial means for varying the position of said control signals in relation to a reference point in the cycle and said dial means being calibrated in percent of the cycle for visibly indicating the percentage position of the control References Cited by the Examiner UNITED STATES PATENTS 28 2,926,333 2/1960 Masten 340-40 2,966,671 12/1960 Abbott 235-154 3,056,946 10/1962 Brockett 34035 OTHER REFERENCES PR System, Bulletin 224, Automatic Signal Divi- 11 340 35 Sion, 1956 P Barker 340-40 10 BENNETT G. MILLER, THOMAS B. HABECKER, Darlington 235-454 Examiners. 

1. IN A TRAFFIC SIGNAL CONTROLLER, A CYCLIC SWITCHING DEVICE HAVING A MULTIPLICITY OF POSITION THROUGH WHICH IT IS ADAPTED TO BE ADVANCED FOR OPERATING A TRAFFIC SIGNAL THROUGH A CYCLE INCLUDING A FIRST "GO" SIGNAL OPERATING POSITION AND A SECOND "GO" SIGNAL OPERATION POSITION THROUGH WHICH IT IS ADAPTED TO BE ADVANCED IN RESPONSE TO RESPECTIVE ELECTRICAL CONTROL SIGNALS, FIRST CYCLIC TIMING MEANS FOR PROVIDING RESPECTIVE ELECTRICAL CONTROL SIGNALS SPACED IN A TIME CYCLE FOR NORMALLY ADVANCING SAID CYCLIC SWITCHING DEVICE IN THE RESPECTIVE "GO" POSITIONS WHEN OPERATIVELY CONNECTED TO SAID CYCLIC SWITCHING DEVICE THEREOF, STANDBY SECOND CYCLIC TIMING MEANS FOR PROVIDING RESPECTIVE ELECTRICAL CONTROL SIGNALS AT TWO RESPECTIVE POINTS IN A TIME CYCLE FOR ADVANCING SAID CYCLIC SWITCHING MEANS IN SAID RESPECTIVE POSITIONS WHEN OPERATIVELY CONNECTED TO SAID CYCLIC SWITCHING DEVICE THEREFOR AND INCLUDING MEANS FOR ADJUSTABLY SETTING THE TIME POSITIONS OF SAID RESPECTIVE POINTS FOR THE TIME OF ADVANCE OF THE CYCLIC SWITCHING MEANS INDIVIDUALLY FOR THE RESPECTIVE "GO" POSITIONS WITH RESPECT TO A DESIRED REFERENCE POSITION IN THE CYCLIC OF SAID SECOND CYCLIC TIMING MEANS, SWITCHING MEANS HAVING FIRST AND SECOND RESPECTIVE ALTERNATIVE SWITCHING POSITIONS, SAID SWITCHING MEANS BEING OPERATIVE FOR INTERMEDIATE SWITCHING FROM EITHER OF ITS POSITIONS TO THE OTHER AT ANY TIME DESIRED IN RANDOM RELATION TO SAID REFERENCE POSITION, MEANS OPERATED BY SAID SWITCHING MEANS IN ITS FIRST SWITCHING POSITION FOR SO OPERATIVELY CONNECTING ONLY SAID FIRST CYCLIC TIMING TO SAID CYCLIC SWITCHING DEVICE, MEANS OPERATED BY SAID SWITCHING MEANS IN SAID SECOND SWITCHING POSITION FOR SO OPERATIVELY CONNECTING ONLY SAID SECOND CYCLIC TIMING MEANS TO SAID CYCLIC SWITCHING DEVICE, MEANS OPERATED BY SAID SWITCHING MEANS IN ITS SECOND SWITCHING POSITION FOR OPERATING SAID SECOND CYCLIC SWITCHING MEANS THROUGH ITS CYCLIC INCLUDING SAID REFERENCE POSITION, MEANS MADE EFFECTIVE BY SAID SWITCHING MEANS IN ITS FIRST SWITCHING POSITION FOR OPERATING SAID SECOND CYCLIC TIMING MEANS TO STOP AT SAID REFERENCE POSITION. 